Motor Control Test Research Articles

Biomechanical procedure to assess sleep restriction on motor control and learning.

The analysis of sleep quality during long periods and its impact on motor control and learning performance are crucial aspects for human health. The aim of this study is to analyze effects of chronic sleep restriction on motor performance. It is intended to establish motor control indicators in sleep quality analysis. A wearable actigraphy that records accelerometry, ambient light, and body temperature was used to monitor the sleep habits of 12 healthy subjects for two weeks before performing motor control and learning tests. The day of the motor test, the subjects filled two questionnaires about the quality of sleep (Pittsburgh Sleep Quality Index - PSQI) and sleepiness (Epworth Sleepiness Scale - ESS). Afterwards they performed a coincident timing task that consisted of hitting a virtual target falling on the screen with the hand. An elbow flexion in the horizontal plane had to be performed on the correct time to reach the real target on a table at the same time as the virtual target on the screen. The subjects performed three sets of acquisition and transfer blocks of the coincident timing task. The subjects were clustered in two groups based on the PSQI and ESS scores. Actigraphy and motor control parameters (L5, correct responses, time variance) were compared between groups and experimental sets. The group with better sleep parameters did show a constant performance across blocks of task acquisition while the bad sleeper group improved from the first to the second acquisition block. Despite of this improvement, their performance is not better than the one of the good sleepers group. Although the number of subjects is low and it should be increased, these results indicate that the subjects with better sleep converged rapidly to a high level of performance, while the worse sleepers needed more trials to learn the task and their performance was not superior to the other group.

Evaluating Human Balance Following an Exercise Intervention in Previously Sedentary, Overweight Adults

Previous research suggests that an improvement in body composition could potentially lead to improvement in balance performance in previously overweight individuals. The purpose of this study was to evaluate if an exercise intervention without any specific balance training can lead to an improvement in standing balance. Fourteen overweight, but otherwise healthy adults (nine females, six males) (mean age: 23.5 years; mean height: 1.70 m, mean starting body mass: 94.1 kg) participated in this study. Balance performance was assessed with sensory organization test (SOT) and motor control test (MCT) on the NeuroCom® Equitest™, prior to and after a 10-week exercise intervention. Results revealed significant improvements in the following balance parameters following exercise intervention: eyes open, sway-referenced visual surrounding and platform condition (p = 0.033) for SOT equilibrium scores; SOT center of pressure (COP) sway in the eyes closed condition for anterior-posterior sway velocity (p = 0.006) and in the eyes open sway-referenced condition (p = 0.048). The results of the current study suggest that improved balance performance can result from an exercise intervention without any specific balance directed exercises, but that the results may be limited to the conditions where the somatosensory system plays a larger role in balance maintenance.

Relationship between postural instability and subcortical volume loss in Alzheimer's disease.

The relationship between postural instability and subcortical structure in AD has received less attention. The aims of this study were to assess whether there are differences in the ability to control balance between Alzheimer's disease (AD) and controls, and to investigate the association between subcortical gray matter volumes and postural instability in AD.We enrolled 107 consecutive AD patients and 37 controls. All participants underwent detailed neuropsychological evaluations, T1-weighted MRI at 3 T, and posture assessment using computerized dynamic posturography. We segmented the volumes of 6 subcortical structures of the amygdala, thalamus, caudate nucleus, putamen, globus pallidus and nucleus accumbens, and of hippocampus, using the FMRIBs integrated registration and segmentation tool.All subcortical structures, except for the globus pallidus, were smaller in AD compared with controls on adjusting for age and gender. Falling frequencies in unilateral stance test (UST) and composite scores in sensory organization test (SOT) were worse in AD than in controls. The motor control test did not reveal any differences between groups. On subgroup analyses in AD, the groups with poor performance in UST or SOT exhibited significantly reduced nucleus accumbens and putamen volumes, and nucleus accumbens volume, respectively. The smaller volume of the nucleus accumbens was associated with postural instability in AD (OR [95% CI] 17.847 [2.59–122.80] for UST, 42.827[6.06–302.47] for SOT, all P < .05).AD patients exhibited reduced ability to control balance compared with controls, and this postural instability was associated with nucleus accumbens volume loss. Furthermore, cognitive dysfunction was more prominent in the group with severe postural instability.

Evaluating Perturbations To Human Balance Following An Exercise Intervention In Previously Sedentary, Overweight Adults

PURPOSE: Previous research suggests that an improvement in body composition could potentially lead to a substantial improvement in balance performance in previously obese and overweight individuals (Handrigan et al., 2010; Maffiuletti et al., 2005). However, few studies have evaluated the balance of a person before and after weight loss following an exercise intervention that did not include any directed balance exercises. The purpose of this study was to evaluate if an exercise intervention alone can lead to a substantial decrease in body weight and therefore improvement in standing balance. METHODS: Fifteen overweight, but otherwise healthy adults (9 females, 6 males) (age: 23.5 years; height: 1.70 m, starting body mass: 92.8 kg) participated in this study. Balance performance was assessed with a sensory organization test (SOT) and motor control test (MCT) prior to and after a 10-week exercise intervention. SOT equilibrium scores were analyzed using a repeated-measures ANOVA. RESULTS: Results from the SOT equilibrium (EQ) scores revealed significant differences in the eyes open, sway referenced visual surrounding and platform (EOSRVP) condition (p = 0.033). Post hoc pairwise comparisons for this variable revealed significantly higher SOT equilibrium scores in post-intervention evaluation versus pre-intervention. No other SOT EQ scores were found to be significant (p > 0.05). Also, no significant differences were seen in MCT postural latency scores (p > 0.05). CONCLUSIONS: The results of the current study suggest that an exercise intervention alone without a significant loss in weight and also without any form of specific balance training can lead to an improved balance performance, but that it may be limited to the conditions where the somatosensory system plays a larger role in balance maintenance.

Selective voluntary motor control measures of the lower extremity in children with upper motor neuron lesions: a systematic review.

Recovery and trainability of impaired selective voluntary motor control (SVMC) of the lower extremity in children with upper motor neuron lesions has received little attention. To facilitate an evidence-based debate about this topic, this review evaluates the evidence level of the psychometric properties of SVMC measures. MEDLINE, Embase, CINAHL, PsycINFO, Scopus, Cochrane and PEDro databases were systematically searched up to July 2016. Two independent raters scored the methodological quality in accordance to the COnsensus-based Standards for the selection of health Measurement INstruments (COSMIN) checklist. The overall level of evidence was scored according to Cochrane criteria. We identified 3590 studies, of which 17 were included. COSMIN scores ranged from 'poor' to 'excellent' for studies investigating measurement properties of the Selective Motor Control test, modified Trost test, Gillette's Selective Motor Control test, Selective Control Assessment of the Lower Extremity (SCALE), kinematic measures, electromyography, and torque steadiness. Studies assessing the SCALE scored highest on COSMIN items. Evidence levels for SCALE's validity and reliability properties were moderate, while for the other SVMC measures these ranged from unknown to moderate. Responsiveness was not assessed. Further psychometric studies of SVMC measures are needed to provide a scientific contribution to the ongoing debate of SVMC trainability.

Reliability and validity of a force-instrumented treadmill for evaluating balance: A preliminary study of feasibility in healthy young adults.

Background:With the development of computer technology, computerized dynamic posturography provides objective assessments of balance and posture control under static and dynamic conditions. Although a force-instrumented treadmill-based balance assessment is feasible for balance evaluations, currently no data exists.Objective:This study was undertaken to assess the reliability and validity of balance evaluations using a force-instrumented treadmill.Methods:Ten healthy adults participated in evaluations using both the treadmill and the EquiTest. Four balance evaluations were conducted: Modified Clinical Test of Sensory Interaction on Balance, Unilateral Stance, Weight Bearing Squat, and Motor Control Test.Results:All balance evaluations using the force-instrumented treadmill method shared good reliability (intraclass correlation coefficient ≥0.6). The Modified Clinical Test of Sensory Interaction on Balance, Unilateral Stance, and Weight Bearing Squat evaluations had a correlation of r < 0.5 with EquiTest, whereas the Motor Control Test balance evaluation had moderate correlations (r > 0.5) with the EquiTest.Conclusion:The results demonstrated that all balance evaluations using the force-instrumented treadmill were reliable, and that the Motor Control Test evaluation was moderately correlated with the EquiTest. Therefore, the use of a force-instrumented treadmill in balance evaluations might provide a certain level of value to clinical practice.

Development of an Instrument to Measure Planter Seed Meter Performance

Abstract. A compact and portable device would be useful for the efficient measurement of the performance characteristics of planters. The performance measurement is accurately achieved by detecting and acquiring the data from a seed sensing component, as well as seed meter rotation by a motor control component. An instrument for measuring planter seed meter performance was developed to compute the percentage of seed singulation, skips and multiples along with the coefficients of variation of seed placement. The instrument was evaluated under laboratory condition. A seed detection test showed that the system did not miss counting any seed at the 25 cm seed spacing under any traveling speed, and the counting rate was 99.03% at the 15 cm seed spacing with the higher traveling speed of 12 km/h. A motor control test showed that seed meter rotation was very precise. There was no measurable angle error after 100 revolutions when traveling speed was 6 to 12 km/h, and only 1° angle error after 100 revolutions when traveling speed was 4 to 5 km/h, possibly due to gearbox vibration at lower speeds. The developed instrument was compared with an existing belt-based measurement system under traveling speeds of 4, 6, 8, and 10 km/h, and the results showed that the developed instrument had the same level of accuracy as the belt-based system but with much faster speed and better compactness. Finally, four types of seed meters (Precision Finger Meter, vSet Vacuum Meter, Hebei Finger Meter, Jiamusi Vacuum Meter) from different manufacturers were evaluated under traveling speeds of 3 to 12 km/h using the developed instrument, and the results were qualitatively analyzed and consistent with their published specifications.

Improving Balance through Virtual Reality and Physical Therapy Integration

Background and Purpose: Virtual reality (VR) is an innovative technology that shows promise in the assistance of physical therapy (PT). This case report explores the use of virtual reality with a patient suffering from unilateral vestibular hypofunction (UVH). Case Description: The patient is a 50-year-old male who was referred to physical therapy following a motor vehicle accident. The patient was diagnosed with having an acute left UVH, accompanied by reports of dizziness, imbalance and gait disturbances which impaired him from his work in construction. Intervention: The patient was seen two to three times a week for 40-minute sessions along with an individualized home exercise program. Interventions included vestibular rehabilitation exercises, balance training, gait training, and VR. The goals of VR were to provide task-specific simulations to improve postural balance, decrease anxiety through exposure therapy, and improve smooth eye pursuits to improve static balance. Outcomes: Outcomes used included subjective questionnaires such as the Activities-Specific Balance Confidence survey and the Dizziness Handicap Inventory (DHI) as well as functional tests like the Sensory Organization Test, Motor Control Test, and the Functional Gait Assessment (FGA). Outcome measures were performed at initial evaluation, at the 10th visit, and again at discharge. Notable improvements were seen on DHI and FGA scores. Conclusion: Dizziness, confidence, balance, and gait improved following vestibular rehabilitation combined with VR. Outcomes of this case suggest that virtual reality in conjunction with vestibular rehabilitation therapy is effective in improving deficits of unilateral vestibular hypofunction. Additionally, the use of VR in this case report suggests this can be an effective tool for intervention to facilitate patient-specific goals.

Sensory organisation and reactive balance control of amateur rugby players: A cross-sectional study

Purpose: This study compared the sensory organisation and reactive balance control of amateur rugby players and a control group. Methods: Forty-one amateur rugby players (22 males: 19 females; mean height ± SD = 168.8 ± 8.8 cm; mean weight ± SD = 63.9 ± 12.5 kg) and 31 control participants (22 males: 9 females; mean height ± SD = 171.5 ± 10.3 cm; mean weight ± SD = 63.8 ± 10.3 kg) completed the study. Their sensory organisation and standing balance performance were evaluated using a sensory organisation test (SOT), and their reactive balance performance was quantified using a motor control test (MCT). The SOT equilibrium scores (ES) and sensory ratios and the MCT motor response latencies were the major outcome measures. Results: The results revealed that compared to the controls, amateur rugby players had lower SOT ESs under different sensory environments (P < .001, = 0.142–0.254) and prolonged reactive motor response times in the MCT (P < .001, d = 0.890). The vestibular and visual ratios were also lower in the rugby group (P = .005, = 0.107 and 0.108, respectively). No significant difference was found in the somatosensory ratio (P = .853, < 0.001) between the two groups. Conclusions: Amateur rugby players demonstrated inferior standing balance performance compared to their non-trained counterparts. They relied less heavily on vestibular and visual inputs to maintain standing balance under different sensory environments. In addition, they reacted more slowly to postural disturbance, reflecting their suboptimal reactive balance ability in standing.

AGE CHARACTERISTICS OF POSTURAL CONTROL COMPONENTS IN WOMEN 55-64 YEARS OLD

The purpose of the study was to reveal age characteristics of the components of postural control in women 55-64 years old. Computer dynamic stabilometrical complex «Smart Equitest Balance Manager» was used for the comprehensive evaluation of the equilibrium function in elderly women. The following tests were used: Sensory Organization Test (SOT), Motor Control Test (MCT), Rhythmic Weight Shift (RWS). On the basis of the analysis of postural control parameters and according to the SOT data, we have found a quality decrease of the equilibrium function in the functional tests 1-4, as well as reduction in the degree of involvement of the somatosensory information in the balance control in women after 59 years. In addition, comparative analysis also revealed a weakening of postural strategy in all six functional tests SOT. However, no age-related changes have been found in the quality of the equilibrium function (functional tests 5 and 6), being the result of SOT assessment, as well as the degree of involvement of visual and vestibular information in the balance control. The analysis of the MCT test has shown deceleration of coordinated motor reactions. RWS test analysis has shown that women from 59 years had a quality deterioration of gravity control center while moving in the frontal and sagittal directions, as well as speed reduction of the gravity center movements in the sagittal direction.

Measurement properties of the upright motor control test for adults with stroke: a systematic review.

BackgroundThe Upright Motor Control Test (UMCT) has been used in clinical practice and research to assess functional strength of the hemiparetic lower limb in adults with stroke. It is unclear if evidence is sufficient to warrant its use. The purpose of this systematic review was to synthesize available evidence on the measurement properties of the UMCT for stroke rehabilitation.MethodsElectronic databases that indexed biomedical literature were systematically searched from inception until October 2015 (week 4): Embase, PubMed, Web of Science, CINAHL, PEDro, Cochrane Library, Scopus, ScienceDirect, SPORTDiscus, LILACS, DOAJ, and Google Scholar. All studies that had used the UMCT in the time period covered underwent hand searching for any additional study. Observational studies involving adults with stroke that explored any measurement property of the UMCT were included. The COnsensus-based Standards for the selection of health Measurement INstruments was used to assess the methodological quality of included studies. The CanChild Outcome Measures Rating Form was used for extracting data on measurement properties and clinical utility.ResultsThe search yielded three methodologic studies that addressed criterion-related validity and contruct validity. Two studies of fair methodological quality demonstrated moderate-level evidence that Knee Extension and Knee Flexion subtest scores were predictive of community-level and household-level ambulation. One study of fair methodological quality provided limited-level evidence for the correlation of Knee Extension subtest scores with a laboratory measure of ground reaction forces. No published studies formally assessed reliability, responsiveness, or clinical utility. Limited information on responsiveness and clinical utility dimensions could be inferred from the included studies.ConclusionsThe UMCT is a practical assessment tool for voluntary control or functional strength of the hemiparetic lower limb in standing in adults with stroke. Although different levels of evidence suggest that the Knee Extension and Knee Flexion subtests may possess criterion and construct validity, the lack of published literature examining content validity, reliability, and responsiveness raises questions regarding the use of the UMCT in routine clinical practice. These key findings highlight the need to further investigate the UMCT’s measurement properties toward enhancing its standardization.

Effects of proprioceptive neuromuscular facilitation on balance, strength, and mobility of an older adult with chronic stroke: A case report

This study described the effects of a proprioceptive neuromuscular facilitation (PNF) program on balance, strength, and mobility in an older adult with chronic stroke. The patient was male, aged 69 years, with right hemiplegia for 17 years, and had diminished balance, balance confidence, lower extremity (LE) strength, and gait velocity. He received 1 h of PNF-based therapy thrice a week for six weeks. Outcome measures were: Mini-BESTest, limits of stability (LOS), Activities-Specific Balance Confidence Scale (ABC), Five Time Sit-to-Stand Test (FTSST), Upright Motor Control Test (UMCT), and 10 Meter Walk Test (10 MWT). The patient improved on the Mini-BESTest (25/28, from 21/28), FTSST (27.47 s, from 30.27 s), UMCT knee extension (moderate, from weak), and 10 MWT (0.82 m/s, from 0.67 m/s); and positive changes in LOS dimensions. PNF was effective in enhancing balance, strength, and mobility in an older adult with chronic stroke and may mitigate falls risk in this population. More research is needed to determine its impact in a larger sample of older people with chronic stroke.

Effect of Yoga practice on reducing cognitive-motor interference for improving dynamic balance control in healthy adults

ObjectiveThe purpose of our study was to investigate the effects of Yoga on reducing cognitive-motor interference (CMI) for maintaining balance control during varied balance tasks. MethodYoga (N=10) and age-similar non-practitioners (N=10) performed three balance tasks including the Limits of Stability test (LOS – Intentional balance), Motor Control test (MCT – Reactive balance), and Sensory Organization Test (SOT –condition 6: inducing both somatosensory and visual conflicts) under single-task (ST) and dual-task (DT, addition of a cognitive working memory task) conditions. The motor performance was assessed by recording the response time (RT) and movement velocity (MV) of the center of pressure (CoP) on LOS test, weight symmetry (WS) of CoP on the MCT test and equilibrium (EQ) of CoP on the SOT test. Cognitive performance was recorded as the number of correct responses enumerated in sitting (ST) and under DT conditions. The Motor cost (MC) and cognitive cost (CC) were computed using the formula ([ST-DT]/ST)*100 for all the variables. Greater cost indicates lower performance under DT versus ST condition. ResultsThe Yoga group showed a significantly lesser MC for both MCT and SOT tests (p<0.05) in comparison to their counterparts. The CC were significantly lower on LOS and MCT test for the Yoga group (p<0.05). ConclusionResults suggest that Yoga practice can significantly reduce CMI by improving allocation and utilization of attentional resources for both balance control and executive cognitive functioning; thus resulting in better performance under DT conditions.

An Attempt of Early Detection of Poor Outcome after Whiplash.

The main concern with whiplash is that a large proportion of whiplash patients experience disabling symptoms or whiplash-associated disorders (WAD) for months if not years following the accident. Therefore, identifying early prognostic factors of WAD development is important as WAD have widespread clinical and economic consequences. In order to tackle that question, our study was specifically aimed at combining several methods of investigation in the same WAD patients at the acute stage and 6 months later. Our longitudinal, open, prospective, multi-center study included 38 whiplash patients, and 13 healthy volunteers matched for age, gender, and socio-economic status with the whiplash group. Whiplash patients were evaluated 15–21 days after road accident, and 6 months later. At each appointment, patients underwent a neuropsychological evaluation, a full clinical neurological examination, neurophysiological and postural tests, oto-neurological tests, cervical spine cord magnetic resonance imaging (MRI) with tractography (DTI). At 6 months, whiplash patients were categorized into two subgroups based on the results of the Diagnostic and Statistical Manual of Mental Disorders as having either favorable or unfavorable progression [an unfavorable classification corresponding to the presence of post-concussion symptom (PCS)] and we searched retrospectively for early prognostic factors of WAD predicting the passage to chronicity. We found that patients displaying high level of catastrophizing at the acute stage and/or post-traumatic stress disorder associated with either abnormalities in head or trunk kinematics, abnormal test of the otolithic function and at the Equitest or a combination of these syndromes, turned to chronicity. This study suggests that low-grade whiplash patients should be submitted as early as possible after the trauma to neuropsychological and motor control tests in a specialized consultation. In addition, they should be evaluated by a neuro-otologist for a detailed examination of vestibular functions, which should include cervical vestibular evoked myogenic potential. Then, if diagnosed at risk of WAD, these patients should be subjected to an intensive preventive rehabilitation program, including vestibular rehabilitation if required.

Efficacy of CDP and ENG in Detecting Balance Impairment Associated With Cerebral White Matter Changes.

To examine the relationship between white matter changes (WMCs) and abnormal balance test results on computerized dynamic posturography (CDP) and electronystagmography (ENG). Also, to compare the utility of CDP with ENG for this purpose. Retrospective case review. Tertiary care referral center. A retrospective review of 137 subjects was conducted. The CDP and ENG results were compared between patients with (80) and without (57) WMCs as detected byT2/fluid attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI). CDP analysis consisted of both sensory organization test (SOT) and motor control test (MCT) results, and ENG analysis included positional, oculomotor, and bithermal caloric testing. Multivariate logistic regression was performed to control for age and hearing loss discrepancies between the two groups. Ninety three percent of patients with WMCs had an abnormal CDP result, as compared with 44% of patients lacking WMCs (p < 0.001). Eighty six percent of patients with WMCs had an abnormal ENG, as did 81% of patients without WMCs (p = 0.435). Multivariate regression analysis maintained that an abnormal CDP result was significantly associated with WMCs when controlling for age and hearing loss (p < 0.001). These findings suggest that patients with cerebral small-vessel ischemic changes are significantly more likely to have an abnormal balance result as detected by CDP, than by ENG. Hence, CDP may be a better study to identify and document patients who have balance dysfunction associated with this central finding. Such identification will permit additional evaluation and treatment based on objective confirmation of balance dysfunction, in this group of balance-impaired subjects who may have normal ENG's.

Predictive Factors for Inpatient Falls among Children with Cerebral Palsy

ObjectiveInpatient falls are of significant concern. The aim of this prospective study was to determine the predictors of inpatient falls among children with cerebral palsy in a rehabilitation hospital. Design and MethodsA total of 93 patients with cerebral palsy were assessed based on history, physical findings, the Selective Motor Control Test, the Gross Motor Functional Classification System, the Berg Balance Scale and the Manual Ability Classification System. Previous history of falls/frequent falls, and any falls which occurred during hospitalization, were recorded. ResultsOf all 93 patients, 25 (27%) fell and 68 (73%) did not fall. The mean age of the fallers (6.3±2.0 years) was lower than that of the non-fallers (8.1±3.9 years). Behavioral problems according to the mother's statement (OR 26.454), not being able to maintain a long sitting position (OR 10.807), ability to balance on knees without support (OR 9.810), a history of frequent falls (OR 4.893) and a negative Thomas test (OR 4.192 fold) were found to increase the risk of inpatient falls. ConclusionsIn these children with cerebral palsy, behavioral problems according to the mother's statement, a history of frequent falls, not being able to maintain a long sitting position, a negative Thomas test, and able to balance on knees without support were associated with the risk of inpatient falls. Children with cerebral palsy may experience inpatient falls. Further studies are required in order to develop prevention programs. Practice ImplicationsFor patients diagnosed with cerebral palsy, these results may help identify possible inpatient fallers on hospital admission.

Normobaric Hypoxia Effects on Balance Measured by Computerized Dynamic Posturography.

Following a familiarization trial, 12 males (27.3 ± 7.1 years) completed three sessions in random order on a NeuroCom SMART Balance Master: a sham trial at the ambient altitude of 1500 m and simulated altitudes of 3000 and 5000 m created by a hypoxic generator. The NeuroCom provided composite scores for a sensory organization test of equilibrium and a motor control test to assess the appropriate motor response. Additional information on somatosensory, visual, and vestibular responses was obtained. Each session consisted of 20 minutes of rest followed by the NeuroCom test, then 10 minutes of exercise, and 10 minutes of recovery followed by a second NeuroCom test, all while connected to the hypoxic generator. Mean differences were identified with a two-way (pre/postexercise and altitude condition), repeated-measures analysis of variance. The composite sensory score was significantly lower (p < 0.001) during the 5000 m trial (73.4 ± 12.0) compared to the 1500 m (80.8 ± 7.0) and 3000 m (84.1 ± 5.0) altitudes. The inability to ignore inaccurate visual cues in a situation of visual conflict was the most common sensory error. Motor control was not affected by altitude or exercise. These results suggest that moderate hypoxia does not affect balance, but severe hypoxia significantly reduces equilibrium. Furthermore, it appears that the alterations in equilibrium are primarily from impairments in visual function.

Reliability and Validity of Force Platform Measures of Balance Impairment in Individuals With Parkinson Disease.

Complex movement and balance impairments in people with Parkinson disease (PD) contribute to high fall risk. Comprehensive balance assessment is warranted to identify intrinsic fall risk factors and direct interventions. The purpose of this study was to examine the psychometric properties of 3 balance measures of a force platform (FP) system in people with PD. Forty-two community-dwelling individuals with idiopathic PD completed the testing protocol. Test-retest reliability was assessed for the Limits of Stability Test (LOS), Motor Control Test (MCT), and Sensory Organization Test (SOT). Intraclass correlation coefficients (ICC [2,1]) were calculated to determine test-retest reliability and minimal detectable change. Validity was assessed by comparing the FP measures with criterion gait and balance measures using Pearson product moment correlations. Multiple regression analyses examined the contribution of PD characteristics to FP measures. All primary FP variables demonstrated excellent test-retest reliability (ICC=.78-.92). The SOT and LOS demonstrated fair to good correlations with criterion measures, whereas the MCT had fair correlations to balance measures only. Both SOT composite equilibrium and MCT average latency were moderately associated with disease severity. This study's sample had a relatively small number of participants with a positive fall history, which may limit the generalizability of the findings. This study's findings provide support that FP measures are reliable and valid tests of balance impairment in people with PD. Disease severity was significantly associated with SOT and MCT measures, perhaps reflecting that these tests are meaningful indicators of decline in postural control with disease progression. Force platform measures may provide valuable quantitative information about underlying balance impairments in people with PD to guide therapeutic interventions for fall risk reduction.

Impact of alternative footwear on human balance

Alternative footwear are those that are most commonly used for casual or recreational purposes, over the course of the day. The purpose of this study was to examine the effects of three forms of alternative footwear (thong style flip-flops, clog style Crocs®, and Vibram Five-Fingers®) on balance with a low-intensity workload. Eighteen healthy male adults (age: 22.9 ± 2.88 years; height: 179 ± 6.0 cm; mass: 81.3 ± 8.8 kg) participated in this study. Balance performance along with electromyographic (EMG) measures was assessed with sensory organization test (SOT) and motor control test on the Neurocom Equitest, while donning alternative footwear, prior to and after a one-mile walk at a self-selected pace. Sway velocities and root-mean-square sway, SOT equilibrium scores, postural response latencies, and EMG measures from lower leg muscles were analysed using a 3 × 2 (footwear × time) repeated-measures ANOVA. Results from balance variables revealed a significant main effect difference for footwear in the eyes closed and eyes open sway-referenced vision conditions and a significant main effect difference for time in the eyes open, eyes open sway-referenced vision, and eyes open sway-referenced platform conditions. Pairwise comparisons revealed MIN demonstrating significantly greater balance performance in the pretest condition and the post-test demonstrating significantly lower balance performance. Greater balance performance from MIN could be attributed to the barefoot design suggesting an increase in somatosensory feedback from the plantar surface, particularly during absent or conflicting visual feedback. The lower balance performance seen in post-test could be attributed to the one-mile walk, suggesting that even a transient physiological workload could be sufficient to cause balance decrements in alternative footwear.

HSF1-deficiency affects gait coordination and cerebellar calbindin levels

Heat shock proteins (HSPs) play an important role in cell homeostasis and protect against cell damage. They were previously identified as key players in different ataxia models. HSF1 is the main transcription factor for HSP activation. HSF1-deficient mice (HSF1−/−) are known to have deficiencies in motor control test. However, little is known about effects of HSF1-deficiency on locomotor, especially gait, coordination. Therefore, we compared HSF-deficient (HSF1−/−) mice and wildtype littermates using an automated gait analysis system for objective assessment of gait coordination. We found significant changes in gait parameters of HSF1−/− mice reminiscent of cerebellar ataxia. Immunohistochemical analyses of a cerebellum revealed co-localization of HSF1 and calbindin in Purkinje cells. Therefore, we tested the hypothesis of a potential interconnection between HSF1 and calbindin in Purkinje cells. Calbindin levels were analyzed qualitatively and quantitatively by immunohistochemistry and immunoblotting, respectively. While quantitative PCR revealed no differences in calbindin mRNA levels between HSF1+/+ and HSF1−/− mice, calbindin protein levels, however, were significantly decreased in a cerebellum of HSF1−/− mice. A pathway analysis supports the hypothesis of an interconnection between HSF1 and calbindin. In summary, the targeted deletion of HSF1 results in changes of locomotor function associated with changes in cerebellar calbindin protein levels. These findings suggest a role of HSF1 in regular Purkinje cell calcium homeostasis.